1. Field of the Invention
This invention relates to methods and systems for providing digital maps, and more particularly toward a method and system for enhancing digital map content with information provided by one or more third party sources.
2. Related Art
The use of digital geographic or map data has become commonplace in modern society. Commonly referred to as “electronic maps” or “digital maps”, this type of data is now used in a wide variety of applications, such as land-based vehicular navigation, route planning, etc. Internet-based business-to-consumer (B2C) companies now use digital maps to direct customers to theaters, stores, restaurants, and other commercial businesses. Digital maps are also often used in commercial settings, for example, to calculate routes for delivery drivers, or to provide directions for emergency and medical crews to follow when responding to emergency calls.
Increasingly, digital map providers have become gatherers and organizers of an ever greater variety of map data, including for example street addresses, transportation networks, water bodies, parklands, political districts, census data, demographic information, commercial businesses, and entertainment facilities. At the same time, the variety of uses for this map data has also expanded to include such applications as in-car driving assistance, cellular phone-based navigation, locally-focused news, media, and yellow-page information services. With this increase in content and utility, it has become evident that combining the underlying map data with other sources of location-related information can provide a more useful end-product.
A typical approach to map data integration is to create “overlay maps”, in which a digital map is used as a base map, and then additional information from one or more sources is laid over the base map to provide at least an illusion of a more complex map. This is the approach used in many Internet-based map information systems. For example, if a company wishes to provide an online restaurant-search utility, they can provide a base map “A” (which can be a typical map with streets, parks, and other such locations). They can then overlay a second map “B” that contains restaurant information and reviews. Maps A and B may or may not come from the same source and provisioning to a user may or may not be done independently. In response to a user request for a restaurant-map, the company can display a portion or all of map A overlaid with a portion or all of map B, such that the matching restaurants are pinpointed as flags on the map. This process can be extended to overlay many maps atop the base map, giving the perception of a very information-rich map.
However, a problem with this technique is that maintaining consistency between the various maps to be integrated is difficult because map information is being integrated from different sources. When a single application uses information gathered from a variety of data collection efforts, there is a risk of losing consistency. This risk is present even if the data is collected from in-house resources, but is magnified when the data is collected from third parties. One approach might be to maintain or store all of the desired information in a common repository or database. However, as increasing amounts of data are added the database could become quite complex and cluttered, so that performance and maintenance requirements would become unacceptable. In many instances, the third-party is also the entity that is most capable of maintaining the accuracy and freshness of their particular data. This accuracy could be lost if the data is integrated into a monolithic database that no longer receives frequent updates from the original data source.
These considerations of accuracy and consistency come increasingly into play when the issue of geospatial data is considered. For example, a hotel chain that is trying to attract customers considers it extremely important to provide their customers with accurate directions. For some, an interactive local map may be one of their most important sources of advertising. Local knowledge is also considered the best knowledge when it comes to representing local information, such as neighborhood or community information. In each of these instances, a third-party generating its own local data may be better suited to create and update locally-oriented or focused data, than might a centralized map data company operating a single database.
Despite the disadvantages of centrally-stored or monolithic map databases, if a company is to provide the end user with the desired integration of information from a variety of data sources, there must still be some form of central coordination of this data guaranteeing that the data collection efforts are standardized and comprehensive.
One example of a prior attempt to address these issues generally is described in US Publication No. 2008/0215524 by Fuchs et al., published Sep. 4, 2008, the entire disclosure of which is hereby incorporated by reference. Fuchs et al. discloses a “Virtual Database System” (VDB) in order to balance the apparently opposing considerations between allowing integration of map data from various sources in a consistent manner, while simultaneously ensuring that the entity best able to support a particular data source retains control over that data. The VDB allows sharing of control and ownership (or in some instances delegating control and ownership) for each geocoded object that will go into the final overall map product between a digital map provider and one or more third-parties, or between several third-parties. In accordance with an embodiment, the VDB environment enables third-party data providers to easily associate or geocode their data (referred to as “third-party-files”) onto a digital map provider's “base map” or “file-of-reference”, thereby allowing for the creation of dynamic relationships between digital map features and other third-party data providers. The VDB can also be accessed by application providers to purchase and retrieve seamlessly integrated data from multiple vendors through a single mechanism, and then provide that data to an end user. In certain embodiments, the integration can be performed in a dynamic or real-time fashion, receiving up-to-date information from the various sources, creating links, and composing virtual maps, as needed or on-demand. An additional benefit is that, since the information is linked between the map providers and the various third parties, whenever an item of information or a link between items is updated in either the file-of-reference or in one of the third-party files, that updated information can be propagated back to all of the third-parties for further use by them in their own software applications.
Despite these advances in the art, there remains a need to identify and resolve duplicate objects as they appear. Navigation system suppliers and others in the industry may prefer that the map vendors solve this issue within their map products, i.e., prior to compilation into a Navigation Data Standard (NDS) or other physical storage format (PSF). Due to advancing concepts for connected and social navigation, including content personalization and user-defined content downloads, map vendors find it increasingly difficult to guarantee content uniqueness with persistent reliability. There is therefore a need in the art to provide systems and methods by which content from multiple sources can be assessed for duplicates, and by which priorities can be assigned to found duplicate objects so that the most reliable/rich information only is ascertained for actual use, such as presentation for display, and/or later use by flagging or logging said established information.